[langsoul-com]

One big thing is that Vercel owns Nextjs and has started to do direct integrations with their platform.

Although the features can work without Vercel, it's a second class citizen.

The more popular Next is, the less reason people would choose netlify over nextjs as a default option.

[Rapzid]

Oh and some of the React core team landed at Vercel, and React has been focusing on backend features and partnering with Next/Vercel on early development of said features.

So there is frustration that the React project is now perhaps an extension of Vercel's interests, and focused on helping them sell hosting.

Never ending drama in VC land.

[throwup238]

They also employ Svelte’s creator/maintainer.

[james-revisoai]

What features struggle to work self-hosted?

It was my (perhaps outdated) experience that in fact some elements of JS (like using scraper libraries) would not work on Vercel at the time due to memory of serverless function and other limits. But locally they worked on my dev machine.